MRC1 and neoplasm: The expression levels of tumor promoting M2 markers: Cox 2, uPA, MMP9, MMR, arginase and VEGF are significantly higher in Mθs sorted from LLC tumors of WT while Mθs sorted from Rac2-/- mice displayed higher levels of proinflammatory cytokines, which are considered as M1 markers; IL1 and TNFα (Figure 4C).